Horlicks Tablets Are you sure that you are thinking about Horlicks tablets?, I don't ever remember them having a chocolate flavour orthem being packaged in a bottle, Horlicks tablets were always a malted milk flavour, in the form of a flat oblong shaped tablet, they came as a single roll or 2 rolls in a small flat tin.
I think that you are confusing them with Ovaltine tabets that were a small round disc and came in a small brown coloured bottle.